Integrated circuit devices may include circuitry or logic elements that may be used to perform any of a variety of functions. Occasionally, the logic elements may be placed or grouped according to their functionality or operating voltages. An integrated circuit device may thus be partitioned into different logic regions and voltage islands.
As an example, each voltage island may operate at a different voltage level and switches may be used to turn each voltage island on and off. For example, depending on application requirements, certain voltage regions or voltage islands may be turned on while other voltage regions may be turned off. Switches may also be used to tune the performance or power level for a logic region, which may in turn reduce power leakage and optimize performance of the device.
Generally, switches may need to be placed within their respective logic regions. As an example, a switch that controls a specific logic region is generally placed within that region. Accordingly, the area of a particular region may need to be sufficiently sized to accommodate the placement of the switch. Furthermore, depending on the placement of the logic regions and their respective power sources, the switches may need to be sufficiently large to mitigate potential IR drop (also known as voltage drop) problems. As such, additional area on the integrated circuit may need to be reserved for the switches.